iommu: Introduce new 'struct iommu_device'

This struct represents one hardware iommu in the iommu core
code. For now it only has the iommu-ops associated with it,
but that will be extended soon.

The register/unregister interface is also added, as well as
making use of it in the Intel and AMD IOMMU drivers.

Signed-off-by: Joerg Roedel <jroedel@suse.de>

1 files changed, 35 insertions, 0 deletions

diff --git a/include/linux/iommu.h b/include/linux/iommu.h
index 085e1f0e6c07..900ddd212364 100644
--- a/include/linux/iommu.h
+++ b/include/linux/iommu.h
@@ -204,6 +204,26 @@ struct iommu_ops {
 	unsigned long pgsize_bitmap;
 };
 
+/**
+ * struct iommu_device - IOMMU core representation of one IOMMU hardware
+ *			 instance
+ * @list: Used by the iommu-core to keep a list of registered iommus
+ * @ops: iommu-ops for talking to this iommu
+ */
+struct iommu_device {
+	struct list_head list;
+	const struct iommu_ops *ops;
+};
+
+int  iommu_device_register(struct iommu_device *iommu);
+void iommu_device_unregister(struct iommu_device *iommu);
+
+static inline void iommu_device_set_ops(struct iommu_device *iommu,
+					const struct iommu_ops *ops)
+{
+	iommu->ops = ops;
+}
+
 #define IOMMU_GROUP_NOTIFY_ADD_DEVICE		1 /* Device added */
 #define IOMMU_GROUP_NOTIFY_DEL_DEVICE		2 /* Pre Device removed */
 #define IOMMU_GROUP_NOTIFY_BIND_DRIVER		3 /* Pre Driver bind */
@@ -361,6 +381,7 @@ const struct iommu_ops *iommu_ops_from_fwnode(struct fwnode_handle *fwnode);
 struct iommu_ops {};
 struct iommu_group {};
 struct iommu_fwspec {};
+struct iommu_device {};
 
 static inline bool iommu_present(struct bus_type *bus)
 {
@@ -558,6 +579,20 @@ static inline void iommu_device_destroy(struct device *dev)
 {
 }
 
+static inline int  iommu_device_register(struct iommu_device *iommu)
+{
+	return -ENODEV;
+}
+
+static inline void iommu_device_set_ops(struct iommu_device *iommu,
+					const struct iommu_ops *ops)
+{
+}
+
+static inline void iommu_device_unregister(struct iommu_device *iommu)
+{
+}
+
 static inline int iommu_device_link(struct device *dev, struct device *link)
 {
 	return -EINVAL;